Dame Julie Andrews has revealed she once cheekily re-enacted a famed scene from The Sound Of Music without realising a group of tourists were on hand to see it.

The actress - who starred in the film as Maria, the governess to the Von Trapp family - thought she was alone when she burst into song on what she believed was a deserted Swiss hillside.

But in an interview for BBC1's The Graham Norton Show, she said that moments later she realised she had an audience.

Dame Julie, 78, said: "I had to get fit for a role so I used to go to Switzerland and I was walking around in the mountains. One day I thought, 'This is ridiculous, there's not a soul around' and I sang The Hills Are Alive - just as a whole bunch of Japanese tourists came over the hill. You should have seen their faces."

She also told how she turned the air blue while working on wholesome children's film Mary Poppins after a mishap while she was filming a flying scene.

Dame Julie told presenter Graham: " I was hanging around on a very high wire in an excruciating harness and I felt it drop by about a foot and I thought, 'Oh my god, my luck is running out. This is it'.

"I called down to say let me down easy and the word went down the length of the studio. At which point I dropped like a ton of bricks to the stage. There was a silence and I let fly with a few good Anglo-Saxon four-letter words that Disney had never heard before."

Other guests on the show, to be screened at 10.35pm on Friday May 23, include Pharrell Williams and Hollywood stars Jonah Hill and Channing Tatum.